1. Field of the Invention
The present invention relates to an apparatus and method for making markings on ground surfaces such as turf playing fields and fairways. The invention has particular although not exclusive application where there is a need to automatically produce signs, such as logos or advertisements for example, on large ground surfaces whether even, sloped or undulating.
2. Discussion of the Background Art
A variety of arrangements for marking turf, such as the turf of playing fields, are known in the prior art. The simplest turf marking involves the application of straight lines to demarcate playing field boundaries. Commercially available line marking machines are used to facilitate such marking. Such machines may include a line of sight guide to aid the operator in producing a straight line between two reference points. Line marking machines are not suitable for producing complex signs or logos on turf.
Over the last two decades there has been a trend to mark playing fields with signs such as corporate logos or advertisements. High profile sporting events attract large crowds and television coverage so that turf advertisements are effective as such events are viewed by a large audience.
One way in which signs have traditionally been produced on turf has been with the help of stencils having apertures through which paint is sprayed or otherwise applied. The production and application of stencils for creating complex and large turf markings is time consuming and prone to error.
The surface of grounds such as sporting fields typically include variations in surface level, such as for drainage purposes. These variations can vary from tens of centimetres and upwards across conventional sporting fields. Large variations or undulations can cause distortion of logos and possibly affect viewing by spectators. On a golf course there are deliberate variations and undulations in ground surfaces, which exacerbate problems with application and viewing of ground markings. Hitherto it has not been widely known to automatically apply complex markings to ground surfaces, especially to turf which is non-planar, undulating or uneven, since neither of the previously discussed approaches to the generation of turf markings are particularly suited to application on a non-planar or sloping surface.